shepheard



(No Model.)

J. H. SHEPHEARD.

ROD PACKING.

No. 468,730. Patented Peb. 9, '1892.A W

lNvEn-ron:

WITNE'ssS:

JHN H. SHL'PH .ARD,

ATTORNEY.

mm., wmnmmaN n e UNITED STATES PATENT OEEIcE.

JOHN H. SHEPI-IEARD, OF ALBANY, NEW YORK, ASSIGNOR OF ONE-HALF TO ROBERT O. BLAOKALL, OF SAME PLACE.

ROD-PACKING.

SPECIFICATION forming part of Letters Patent No. 468,730, dated February 9, 1892.

' Application ned June 6,1891. serai No. 395,362. (No moda Y To all whom t may concern.-

Be it known that I, JOHN H. SHEPHEAED, of the city and county of Albany, in the State of New York, have invented new and useful Improvements in Packing for Valve-Rods of Steam-Engines and for other Similar Purposes, of which the following is a specification.

My invention relates to improvements in packing for rods of steam-engines, pumps, and other machines whose reciprocating rods require to be provided with a packing to prevent the leakage of steam or other fluids; and the object of my invention is to provide a simple, durable, and eiicient packing for such purposes. This object I attain by the means illustrated in the accompanying drawings, which are herein referred to and form part of this specification, and in Which Figure l is a longitudinal section of my invention applied to the valve-rod of a steamengine when the steam-chest is specially made for the purpose. Fig. 2 is a like section showing the inode of applying my invention to a steam-chest provided with an ordinary form of stufiing-box for the valve-rod. Fig. 3 is a plan view of the construction shown in Fig. 2. Fig. 4 is an enlarged longitudinal section of the cylindrical sleeve and packing-head of my invention applied to a valve-rod, a slight modification of the form of said packing-head being shown in said figure. Fig. 5 is atransversesec` tion of Fig. 4;, showin gtheinner end of the packin g-head, said section being taken at the lineX X; Fig. 6 is a transverse section at the line YY of Fig. 4. Fig. 7 is a longitudinal section of a modified form of the packing-head adapted to use with concentric packing-rings, and Fig. 8 is a transverse section at the line Z Z of Fig. 7.

s illustrated in the drawings, A designates the steam-chest of an ordinary form of steamengine, B the valve-rod, and O the slide-valve of same.

The steam-chest A is provided with a cylindrical sleeve D, Whose inner end is open to the interior of the steam-chest, andrwhose outer end is open to the atmosphere. Said sleeve should be bored smoothly to a uniform diameter so as to allow a packing-head E to reciprocate freelyback and forth therein. In the form of my invention shown in Figs. 2 and 3 the sleeve D is made separately from the steam-chest A and is fitted to secure to the outer end of the stuffing-box F by the glandbolts G, by which the gland of the stuffingboX had formerly been adj usted. This form of my invention is intended for steam-chests that have been provided with the ordinary and Well-known form of stuffing-box for containing packing, Whereby a steam-tight joint 6o was formed for the valve-rod; but when my invention is used thereon the packing and gland commonly employed are dispensed with. The hole for the valve-rod at the bottom of the stu'liing-box is allowed to remain in its 65 previous condition, so that the steam leaking through said hole can enter the bore of the sleeve D and exert its pressure against the inner end of the packing-head E.

The packing-head E is bored to fit snugly 7o on the valve-rod C, and it is adj ustably secured to the latter by means of a set-screw l, of which there may be one or several, `as the occasion may require. The inner end of the packing-head E, provided with a stuffing-box for containing packing 5 and a gland 6, is tted to screw into said stufling-box so as to compress the packing 5 and thereby form a steam-tight joint that will prevent a leakage of steam through the bore of the packing- 8ov head by disconnecting the valve-rod O from the rocker-arm or other mechanism employed for imparting a reciprocating movement to said rod. The latter can be moved outwardly for the purposeof obtaining access to the set- 8 5 screw l so as to loosen the packing-head EV from the valve-rod C. lVhen that act is accomplished, the packing-head can be drawn out from the sleeve D, thereby affording access to the gland 6 Whenever the packing 5 9o may need adjustment, as shown in Figs. l, 2, and 4. The packing-head Eis provided with several circumferential grooves 7, each containing an eccentrically-bored packing-ring S, which fits snugly into the bore of the sleeve D and forms a steam-tight joint therewith in such manner that a leakage of steam through the bore of said sleeve will be prevented. Each packing-ring 8 is cut through its thinner side and is sprung apart to pass over the body 10o of the packing-head until it is in position to enter one of the grooves 7. When this is attained the ypacking-ring 8 will return to its normal diameter and remain in the groovein Which it Was entered. This form of packing has been used for piston-heads with success for many years. Thereforel do not claim it as my invention.

In Figs. 7 and 8 a modified form of packing-head is shown, the same being designated as E. In the latter form the inner extremity of the packing-head is reduced in diameter, as at 9, to form a circumferential rabbet for receiving the metallic packing-rings of a cornmon and well-known form, consisting of two outer rings lO and a single inner ring Il. When made in the latter form, the gland l2 for the stufiug-box of the packing-head E formsa follower for the packing-rings. Preferably said gland is provided With minuteA openings 13 for the purposeof admitting steam toen-terthe space formed between the inner side of thepacking-rings and the periphery of thepacking-head, thereby effecting the expan-V 'sionfof the packing-rings by steam-pressure.

inyention operates in the following man-4 ner: The packing-rings in the packing-heady the pressure of the steam acting uponthe in-- ner end of said packing-head Will push the valve-rod and its 'connected parts outwardly, and thereby any lost motion between the valve,- rnovilng mechanism and the valve-rod will be taken up and all thumping or rattling incident to such lost motion Will be entirely avoided.

I do not confine myself to the precise kind ofv packing for the periphery of the packinghead herein shown and described, as I am aware that -the same results can be produced by the employment of other packings for said packing-head.

.I am aware that rod-packings have heretofore been constructed to embrace a packinghead provided with metallic rings and itted to reciprocate in an open-ended cylindrical sleeve. Therefore I do not broadly claim such constructions; but in thosel earlier constructions, Where the packing-head Was made as an independent part of the. mechanism, no provision was made for preventingan; escape of steam between the bore of the packinghead and the periphery of thevalve-rod.

What I claim vas my invention, andl desire to secure by Let-ters Patent, isy A rod-packing consisting of apacking-head which is adjustably attachable t oarecipro cating rod and tted toreciprocate in a cyling drical' sleeve, said packing-head being providedvwith metallic packing-rings on itsfperiphery and with a stuftingfbox for receiving packing between the boreof said packinghead and the rodto which it is attached, the inner end of said packing-head being exposed tothe iii'liId-pressure, substantially asvherein specified.

.IOIIN Il. SHEPHEARD.

Witnesses:

CLARENCE STAEWELI# WM. H. LOW. 

